think the only people that she justified genocide for is the mythalans. And they already were extremely anti-sharonian. I suspect that without the religious connotations the mythalans affix to magic, places like andara and ransar will react with fear of the unknown but also with a desire to understand.
In a certain sense I disagree. Think of it this way: Arcanan society has revolved around and advanced through the use of magic. It is ingrained in every day life. How do you think they would react if a group of unknown people came along and can, by unknown means, shut off magic(or at the very least mess with it) without any explanation. I would imagine they would react poorly to that, regardless of national lines.
Granted, there will still be people will hold to the value of human life, particularly in the Ransaran and Garthan camps, but the Andarans will be split down the middle with the side who has lost faith in the old codes of honor of Andara maybe having a majority in numbers, and we saw at the beginning of the war, straight out of the gate they were more than willing to commit crimes against humanity.
To summarize, I think at least most of Arcanan society will be atleast somewhat sympathetic to the Mythalan's sentiment, if not outright their actions.